Abstract

In electromyography fine wires are inserted into muscles to measure their activity periods. We have employed this technique to evaluate the activity of various muscles of the nasolaryngeal system of dolphins during the production of sounds. The anterior internus, the posterior internus, diagonal membrane muscle and the nasal plug muscle have been studied in greatest detail. These muscles fire just before and during the production of sounds whereas the hyoepi-glottal muscle and the intercostal muscles do not. Simultaneous video recordings of blowhole movement and electromyogram (EMG) have been made to correlate such movement with EMG and sound production.

Green, R. F., Ridgway, S. H., and Evans, W. E., Functional and descriptive anatomy of the bottlenosed dolphin nasolaryngeal system with special reference to the musculature associated with sound production, this volume.Google Scholar